Huawei's second Windows Phone 8 handset, the Ascend W2, seems to be the company's worst-kept secret, repeatedlybeing outed, and yet still remaining officially unannounced. Last month, we noted that leaked images of the device had buttons with different colour illumination, speculating that each colour variant of the handset might have button backlighting to match its outer shell.

The reality is even cooler than that, as the latest images from WP7forum.ru show. While the handset is indeed offered in different colours - we've seen blue, yellow and red options so far - the device actually features buttons that change colour depending on the theme you've chosen in the OS. If you opt for a red OS accent colour, for example, the button backlighting will change to match your choice.

Engadget managed to grab some video of the device, including a short section (from 0:52 to 1:04) showing the changeable backlighting in action:

The Ascend W2 will be a relatively low-end device when it (eventually) goes on sale, with a 1.4GHz dual-core CPU, 8GB of storage, 512MB of RAM and a 4.3-inch WVGA (800x480px) display. While it's unlikely to get anyone particularly excited by its specs, the variable colour backlighting is a nice differentiating feature.

The handset is expected to launch in the next few weeks, although we're still waiting to hear how it will be priced. The Ascend W2 will be the company's second Windows Phone, following on from the Ascend W1. Earlier this year, a Huawei executive told Neowin that a high-end Windows Phone is also in the works, but we've not heard anything further on that device.